Integrated Buck Converter LDO Combo Saves Power, Reduces PCB Footprint

Santa Clara, CA ¨C October 14, 2008 ¨C Advanced Analogic Technologies Incorporated (AnalogicTech) (Nasdaq: AATI), a developer of power management semiconductors for mobile consumer electronic devices, announced today the AAT2688, an integrated synchronous step-down converter and low-dropout (LDO) regulator for 12V adapter systems. Leveraging the unique advantages of AnalogicTech¡¯s proprietary high voltage Modular BCD process, the new device helps save power and reduces thermal dissipation by delivering efficiency levels up to 90 percent.

¡°Driven by cost considerations, many popular 12V consumer electronics systems such as set-top boxes, WLAN systems and DSL and cable modems, are forced to accept lower than optimal levels of power efficiency,¡± says CJ Zhang, Product Line Vice President at AnalogicTech. ¡°By integrating a synchronous step-down converter with a wide input range and an LDO optimized for low noise and low current, the AAT2688 allows designers to have the best of both worlds - power efficiency up to 90 percent and a dual-output power management solution in a compact, space-saving footprint.¡±

Targeting Low Cost 12V Applications

Channel one on the dual output AAT2688 is a buck converter which operates off a wide 6V-to-24V input voltage making the device ideal for low-cost 12V adapter applications. The buck converter delivers a 4.5A output and converts 12V to 3.3V at a 4.5A load with up to 90 percent efficiency.

A high 490 kHz fixed switching frequency supports the use of small external L/C filtering components. Voltage mode control optimizes operation across the entire output voltage and load range. The buck converter offers accuracy +/- 1.5%.

The second channel on the AAT2688 provides a low input voltage LDO. This function operates off a 2.7V to 5.5V input voltage and delivers up to 600 mA. The LDO combines low output noise and low quiescent current with excellent transient response.

To maximize designers¡¯ options, the AAT2688 provides independent input and enable pins for each function.

To ensure device integrity, the new device also features internal soft start, over-current and over-temperature protection circuits.

Price and Availability

The AAT2688 is qualified across the -40º C to +85º C temperature range. It comes in a 4 x 5-mm, 24-pin TQFN package. The IC sells for $1.25 in 1K quantities.